I currently have a 95 honda del sol which came stock the the B16a engine. Put a LS block in it and now the idleing is jumping in rpm nothing too crazy but it does jump up and down in rpm. I have a stock exhaust with a cat thats clogged.lol havent gotten a chance to change this, im assuming that the reason my be a sensor? I have a DC sports ceramic 4-2-1 header. I got the car not too long ago and many of the performance parts were already on the vehicle.It pulles really hard on take offs but it think it should perform better. It was a champ for having a stock B16a against the competitors that I raced against. but now it seems to be not much more impressive.Heres an example why I think this: just the other day with my LS/vtec motor I raced a honda civic with a LS non vtec motor and I didnt pull on him that hard. the funny thing is i raced a older honda that was lighter than my car with a non vtec LS motor swap in it; when I had my B16a and beat him and pulled on him about the same as i did with my motor swap! What the hell is going on!? Theres something not right. Im just not sure what. Can you help me please! what is your suggestion?